PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       ftell, ftello — return a file offset in a stream

SYNOPSIS

       #include <stdio.h>

       long ftell(FILE *stream);
       off_t ftello(FILE *stream);

DESCRIPTION

       The functionality described on this reference page is aligned with the ISO C standard. Any
       conflict between the requirements described here and the ISO C standard is  unintentional.
       This volume of POSIX.1‐2017 defers to the ISO C standard.

       The ftell() function shall obtain the current value of the file-position indicator for the
       stream pointed to by stream.

       The ftell() function shall not change the setting of errno if successful.

       The ftello() function shall be equivalent to ftell(), except that the return value  is  of
       type off_t and the ftello() function may change the setting of errno if successful.

RETURN VALUE

       Upon  successful  completion,  ftell()  and ftello() shall return the current value of the
       file-position indicator for the stream measured in bytes from the beginning of the file.

       Otherwise, ftell() and ftello() shall return -1, and set errno to indicate the error.

ERRORS

       The ftell() and ftello() functions shall fail if:

       EBADF  The file descriptor underlying stream is not an open file descriptor.

       EOVERFLOW
              For ftell(), the current file offset cannot be represented correctly in  an  object
              of type long.

       EOVERFLOW
              For  ftello(), the current file offset cannot be represented correctly in an object
              of type off_t.

       ESPIPE The file descriptor underlying stream is associated with a pipe, FIFO, or socket.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       Section 2.5, Standard I/O Streams, fgetpos(), fopen(), fseek(), lseek()

       The Base Definitions volume of POSIX.1‐2017, <stdio.h>

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1-2017,  Standard  for  Information Technology -- Portable Operating System Interface
       (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C)  2018  by
       the  Institute  of  Electrical  and Electronics Engineers, Inc and The Open Group.  In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard,  the  original  IEEE  and  The  Open Group Standard is the referee document. The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .